Australia & New Zealand: Water deficits across northern Australia & Tasmania; North Island, New Zealand

The Big Picture
The forecast through December 2016, as seen in the composite 12-month map (below), indicates the presence of persistent water deficits across the north and in Victoria, Tasmania, and North Island, New Zealand.*

Impacts
Australia's March mean temperature was the warmest on record and Tasmania recorded its longest marine heatwave ever - from December 3, 2015 and ongoing as of April 17, 2016. In its April 8 rainfall report the Australian Government Bureau of Meteorology stated that "Serious to severe deficiencies persist in western and central Victoria and in western Tasmania." The state government of Victoria has promised to fund a $87 million pipeline and a $27 million drought package. Low dam levels in Tasmania along with a breakdown of Basslink - the cable that enables the state to import power from the mainland - have thrown Tasmania into an energy crisis that has triggered a Senate inquiry. Farther north, caravans of volunteer "hayrunners" are trucking bale-loads worth up to $6 million to support drought-stricken graziers in western Queensland.

Forecast Breakdown
The 3-month composite (below) for the same 12-month period shows the evolving conditions in more detail. Deficits across much of Australia are forecast to diminish, with the exceptions mentioned above and from Perth southward where deficits will continue to emerge. A transition from moderate deficits to moderate surpluses in easternmost tributaries of the Darling and Murray Rivers is evident in the October through December map. Current surpluses farther north along rivers in eastern Queensland are expected to persist. In North Island, New Zealand exceptional deficits will persist through June, and pockets of moderate to severe deficits will continue to emerge on South Island. Deficits in New Caledonia are forecast to be exceptional and widespread in April, but will diminish thereafter.

(It should be noted that forecast skill declines with longer lead times.)

* Please note that effective March 28, 2016 NOAA changed the initialization procedure for CFSv2 to address issues with unrealistically cold sea surface temperatures in the Tropical Atlantic Ocean. As a result, this month's Watch List is based on an ensemble of 14 CFSv2 forecasts issued after this fix was implemented instead of the normal 28. For more information see http://www.nws.noaa.gov/os/notification/tin16-09cfs.htm and http://www.nco.ncep.noaa.gov/pmb/changes/downloads/CFSv2_Atlantic_cold_bias_problem.pdf.